Chemistry - Atomic structure and the periodic table.

    Cards (19)

    • Atom
      The smallest particle in the universe
    • Atom
      • Has a nucleus
      • Contains protons and neutrons
    • Electron shell

      • Electrons are found here
    • Mass number
      Tells us how many protons and neutrons there are
    • Atomic number
      Tells us how many protons there are
    • The mass number is the bigger number on the periodic table
    • Isotopes
      Atoms with the same number of protons but a different number of neutrons
    • Isotopes have a different mass number but the same atomic number
    • Isotopes are different forms of the same element
    • RAM (Relative Atomic Mass)

      (mass x number) + (mass x number) / total number
    • Periodic table
      • Arranged in groups and periods
      • Rows are periods, columns are groups
    • Electron arrangement

      • Atomic number = amount of electrons
      • 1st shell has space for 2 electrons, 2nd shell has space for 8 electrons, 3rd shell has space for 8 electrons
    • Periods
      Tell us the number of electron shells
    • Groups
      Tell us the number of electrons in the outer shell
    • Elements in the same group have the same chemical properties as they have the same amount of electrons in the outer shell
    • Noble gases

      • Inert as they do not react easily
      • Have full outer shells
    • Halogens
      • Diatomic molecules
      • Very reactive as it is easy to gain another electron
    • Alkali metals
      • Only have 1 electron in their outer shell
      • Reactivity increases going down the group
      • Outer electron becomes further apart from the nucleus, weakening the force of attraction
    • Alkali metals reacting with water

      1. Form hydrogen gas
      2. Form an alkaline solution